Indeed it may save you in case the malware is being particularly lazy but I think it may do more harm than good by giving people a false sense of security and it can also break packages that use post-install scrips for legitimate reasons.

For anyone who actually cares about supply chain attacks, the minimum you should be doing is running untrusted code in some sort of a sandbox that doesn't have access to important credentials like SSH keys, like a dev container of some sort.

You would still need to audit the code otherwise you might ship a backdoor to production but it would at least protect you against a developer machine compromise... unless you get particularly unlucky and it also leverages a container escape 0-day, but that's secure enough for me personally.